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Speedbrake Deployment & Bounce Landing

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Tested the speedbrakes, this time without cutting the trottles manually, A/T and SPD all the way down. I also had speed @ REF +5 = 133, no bounce and perfect deployment, I had not even engaged REV yet here in these shots.. http://forums.avsim.net/user_files/86681.jpghttp://forums.avsim.net/user_files/86682.jpghttp://forums.avsim.net/user_files/86683.jpgBest Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Yay !! Can't wait to get home from work now !!!Regards,

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Two flights last night, spoilers deployed flawlessly and AT Disc worked perfect! Bravo PMDG Bravo !!Blue Skies,

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So this means no manual disengage from A/T anymore? Just arme the spoilers and FLY! (Or do I have to say LAND!) :)Is this only in -800/900 series?Regards,Steven

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Well this is the 700 here I was flying. I use to manually push F1 before T/D to assure SB deployment, but as you can see this is no longer needed as long as your controller is calibrated correctly ;-). As for the A/T, it has always disconnected on an A/L @ 2 seconds after T/D. Make sure to ARM the SB from the throttle quadrant, not SHIFT / which does not work to ARM..Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Hey,What was your landing weight?DavidP.s. What were the winds at?

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I believe I had abt. 4100 lbs in each wing....Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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36FPS landing at LAX?Who needs speedbrakes at this framerate :)Thanks for the info, will try immediately.

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Hey Randy,Sorry should have clarified, I was looking for the gross landing weight, saying the fuel amount really means nothing if you don't know how much the ZFW was.Also can you try it with some wind and see if that affects it. That skipping I described in the other post happened with about a 9 knot headwind component (landing on 05 winds 080@11)Regards,David

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Radny, for sake of the test, PLEASE do the same thing you did with 900. Because in my two tests, 700 acted as yours did, 900 did not.Please please please. Thx.

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Hmmm,My test was with the 800 ZFW 131.7 FI 8800 wingtanks. Headwind approx 10kts. No bounce, a/t disengaged properly, Spoilers armed at Throttle panel, deployed normally. Simply beautiful, have 3 flights now with the SU and it working flawless. I can post screenies this evening after I leave the grindstone.Regards,

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Hi guys!There is another thing I found out. If you are flying with real wheather, the winds can be some different on several places. This means that the Vref+5kts is at places where the headwind is more than 5 kts to minor for landing. The plane just can't handle enough with the wind. To get the perfect FAS (Final Approach Speed) just take a look at the wind on your destination with ATIS and count out the headwind that will occure. Your FAS will be Vref+headwind Example winds on destination 330/16, landing rny 27 (heading 270)Vref 130FAS=Vref + headwind= 130 + 8= 138ktsIf this is not correct, correct me please. But I think this could solve difficult landings.Regards,Steven

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The airspeed is the speed of the airplane in the air, and has nothing to do with which way or how hard the wind is blowing. You can change the Vref speed to allow for wind gusts, but it should have nothing to do with the direction or velocity of the wind at runway. That will only change your ground speed.

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>The airspeed is the speed of the airplane in the air, and has>nothing to do with which way or how hard the wind is blowing.>You can change the Vref speed to allow for wind gusts, but it>should have nothing to do with the direction or velocity of>the wind at runway. That will only change your ground speed.>>>Yes, but that's the point. The ground speed is too low when bouncing I think. If there is much wind, your ground speed is too low.Regards,Steven

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When winds are below 10knots, use VREF+5When winds are above 10 knots use 0.5 headwind.When winds are gusting, use 0.5 steady wind + gustExample for runway 27Winds 270 @ 14 gusting 200.5x14 + 6 = 13So use VREF + 13Windcomponent has a maximum of 20 knots!Example winds 270 @ 24 gustin 340.5 x 24 + 10 = 22Now use VREF + 20

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Hey all,The 737 autoland system has a wind speed/gust control system inbulit and so when flying a full auto land the speed should be set to Vref+5 only.In other words autolands don't have wind correction added to the Vref speed.Also I done another test flight in the 700 and it bounced/skipped on landing and this time I have many pictures to prove it. I also performed the same test in the 600 and it landed without a skip (I have pictures of that aswell incase of naysayers who suggest those with problems aren't "doing it right" - call me pessimistic!)Details of the 700 flight:ZFW 120454lbs (Max ZFW 120500lbs)Take off gross 8546lbsLanding gross 127.6 (Max landing 128000lbs)Flaps 30 (Vref30=133) Wind none[a href=http://www.ibsw08346pwp.pwp.blueyonder.co.uk/700slideshow/Cache Page.htm]Results[/a] in a slideshow, last slide displays loadmanager. The slides will play in a continuous loop after being started.I'll be performing more tests later and will report back.CheersDavid

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Well some of us "naysayers" happen to fly the real NG (Brad Marsh) so I think they have some weight don't you think Dave? I have flown this bird since day one of it's development so I believe I qualify upon it's handing. It's true that the A/T takes into account the extra **gusts** with the VREF set to + 5. Do you have flaps 40 here Dave? No one doubts that you are indeed bouncing but the question is why you and some others ARE and others like ME are not, we do not have two sims here (as long as we are both using the 800-900 and 600-700 updates). So why not show us the exact same frame by fram of what your cockpit looks like during the same time frame? I think this would be much more helpful to the discussion.Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Let's also keep some things in perspective here regarding bouncing. It happens in real life too. And I believe that some of the real reasons it happens is also why we see it in the sim. Number one reason I believe this happens is for excess speed upon T/D. The plane in your pictures seems to want to spring back right into the air. If your speed was indeed falling (The speed should be right AT or deceling below REF) upon T/D with idle throttles @ 30 RA, speedbrakes out at contact of main gear with ground should in help keep the aircraft firmly upon the ground but only if the speed is indeed correct. Now everyone does things differently, there is no way for us to know how one performs a flight and landing unless one provides detailed information for us to review. It is a fadct some bounce so the next logical step would be to provide all relevent data to show why. This way we can deal with only facts and if there is perhaps something a bit off then it can be shown and most important replicated each and everytime.Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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>> Well some of us "naysayers" happen to fly the real NG (Brad>Marsh) so I think they have some weight don't you think Dave?>I have flown this bird since day one of it's development so I>believe I qualify upon it's handing.I'm talking about the naysayers who dismiss out of hand the fact that some guys are having these problems and simply put it down to pilot error. I'm not doubting the real world pilots, it's the self announced experts that have nothing good to say bar "your doing something wrong" instead of trying to help figure out the reason behind it. If they don't have anything constructive to say they should keep their "superior" comments to themselves and let us plebs try and get down to fixing it.B!tch over!> Do you have flaps 40 here Dave? No, 30

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Randy,I posted the specifics for a flight tonight in my other post here in the PMDG forum titled, "Which Vref To Choose?". Please look there and see how I had the aircraft configured.Thanks!DougDell 8250 (3.06GHz/533FSB)1GB Rambus RAM120MB ATA 100 (7200 RPM)ATI Radeon 9700 Pro (Catalyst 4.5)Audigy 2 Sound (latest drivers)MS Force Feedback 2WindowsXP Pro (SP1)DirectX 9.0b

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P.s. Replyed before I seen the second post:>Number one reason I believe this happens is for excess speed>upon T/D. The plane in your pictures seems to want to spring>back right into the air. If your speed was indeed falling (The>speed should be right AT or deceling below REF) upon T/D with>idle throttles @ 30 RA, speedbrakes out at contact of main>gear with ground should in help keep the aircraft firmly upon>the ground but only if the speed is indeed correct. The engines were winding down, shame pics can't include sound :-)I switched to the outside view just as the 'RETARD' came up on the PFD annunciator so am unsure about the actual speed. Speed was perfect at Vref30+5 all the way down - I monitored the approach to the last minute when I switched to take photos. I can say with 99% certainty that it wasn't going too fast. Just as I write that I've had a though but I'll get back to it later (it's 0500 here).Also note in the pics that the brakes and spoilers don't deploy on the first touchdown (kudos programmers!)>> Now everyone does things differently, there is no way for us>to know how one performs a flight and landing unless one>provides detailed information for us to review. It is a fadct>some bounce so the next logical step would be to provide all>relevent data to show why.As I said before, write me a list of the details you need and I'll get them to you.David

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Thanks David, I will do another fight tonight. I tend to think we somehow have excess speed here. Can you do me a favor and leave the MCP spd to VREF without the correction and tell me if you still have the bounce? I will try it myself...Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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This is all very interesting what you write, I've been trying all morning today to get to the bottom of this, doing small takeoff-turn-land flights up to 4000ft around LOWS. So far I've tested 700, 800 and 900 models, and on all 3 models, speedbrake DID NOT deploy automatically (nor did throttle idled itself in the throttle quadrant upon flare). And aircraft bounced after that. Bounces are slightly different, depending if I set VREF or VREF+5, also angle of attack prior to landing is different. I still have to use F1 to be kinda 80% sure that SB will deploy (also sometimes it doesn't).Considering my joystick, MSFF2, it's calibrated correctly, since the idle throttle yields around 20.3% N1.Any ideas? My machine could handle FRAPS movie, so Randy, if you'd like, I can record the whole flight and then you can see for yourself what I may be doing wrong or if there's some other error...I wish that we once and for all get this to WORK.

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Hey all,I forgot to mention: I am not having any problems with speedbrakes and/or auto throttles. The test route I flew was basically a circuit of the airport that was flown on autopilot from 1000ft to touchdown. I'll post the route if you guys want so that we are singing from the same song sheet.I had the though that I posted on another thread that perhaps the problem at high gross landing weights is that the autothrottles don't have enough time to bring the throttles all the way back to idle through the flare due to the higher thrust settings required to hold the approach speed at the higher weights.i.e. at max landing weight perhaps you need 80% N1 to hold the approach speed (just for talking sake) and at a lower weight you only need 60% N1.Now if the auto thrust system pulls back the throttles at the same time (altitude AGL) and at the same rate then it is obvious that the 80% setting is going to take longer to pull to idle than the 60%.Now, if the 60% hits idle power as the mains touchdown then it is obvious going by the previous statement that there will be 20% power left on in the higher thrust situation upon touch down.This small thrust setting could be enough to cause a skip.What do you guys think?I'll do some flights later at Vref without the +5 and at a lower landing weight. I'll also get some screens of a bounced landing from the cockpit so that you can see the thrust settings etceteraHave a good one,David

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David,I think bouncy landing is only due to too heavy or too fast vertical approach, because if you do it manually, and set the aircraft nicely on the runway, it will not bounce.But I think you might have something on this one...Say, situation you are talking about, is it without A/P, with one A/P or two A/P (full auto-landing)?

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